Device for controlling the suction air supply and the pressure air supply for a sheet processing machine



Feb. 11, 1969 A.,SCHWEBEL 3,426,963

' DEVICE FOR CONTROLLING THE SUCTION AIR SU Y URE D THE AIR SUPPLY F0 SHEET PROCESSI HINE Filed 2, 1967 PRESS PRESSURE 21 SUCTION In van/0r:

RBOLF scuwvaeb United States Patent 3 Claims ABSTRACT OF THE DISCLOSURE A device for supplying suction air consumers and pressure air consumers of a sheet processing machine with suction air and pressure air respectively, and for controlling the supply of suction air and pressure air.

The device provides valve means for selectively bypassing and conveniently separating the suction air consumers and the pressure air consumers from the pump or the compressor while the same continues to operate.

There are known devices to control the sheet feeders of sheet processing machines and other accessories of such machines operated by suction air or pressure air. Such control devices serve to assure a continuous and adequate supply of suction air or of pressure air to operate, for instance, sheet separating means and sheet conveying means of the machine. The devices must be capable of satisfying the demands made on the suction power or the pressure of the used air in accordance with the properties of the specific sheet material to be processed in the machine.

Pump or compressor assemblies as are used for the sheet processing machines generally require very long conduits for feeding the suction air and the pressure air respectively to the suction air or pressure air consuming devices of the machines.

Practical experience shows that the pump or compressor assemblies tend to be heavily loaded and are frequently even overloaded. This is particularly true when the pump or compressor assemblies are only intermittently and abruptly operated, as is the case, for instance, when the machine is initially set up for operation. Overloads also tend to occur when the sheets have to be aligned or be placed in registry at the separating means and the conveying means of the machine.

It is a broad object of the present invention to provide a novel and improved device of the general kind above re ferred to, in which the aforepointed out danger of heavily loading or overloading the pump or compressor assembly is eliminated by relieving the load on the pump or the compressor when the delivery of suction air or pressure air is not required. Obviously such an arrangement has also the advantage that the wear and tear on the pump or the compressor is considerably reduced.

The afore pointed out objects, features and advantages of the invention and other objects, features and advantages which will be pointed out hereinafter, are obtained by providing a valve by means of which a suction conduit and a pressure conduit leading from a pump or compressor to the suction air consumers and the pressure air consumers of the machine can either be both opened for a free flow of suction air or pressure air to the consumers, or the two conduits can be directly interconnected thereby by-passing the consumers and establishing a direct flow path both between the suction side and the compressor side of the pump or the compressor. In other words, the consumers are in effect disconnected from the supply of suction or pressure air without stopping the pump or compressor when the delivery of suction and pressure to the consumers is not needed.

The valve may be a rotary slide valve as will be more fully described hereinafter.

The invention further provides that the valve is designed as a self-contained structural unit so that it can be conveniently mounted at any desired location of the machine, for instance, closely to the sheet separating and conveying means thereof.

In the single figure of the accompanying drawing a preferred embodiment of the invention is shown by way of illustration and not by Way of limitation.

Referring now to the figure more in detail, the figure shows diagrammatically an elevational view of an exemplification of the device according to the invention.

The device comprises a valve 2, shown by way of example as a rotary slide valve. The valve comprises a housing 20, including a cylindrical valve chamber 3. A slide 4 is rotatably mounted in the chamber to define therein two closed compartments 18 and 18a. The slide can be rotated in the chamber by an externally operable activating means, such as a handle 5. Two stop pins 6 and 7 may be provided on housing 20 to limit the angular movement of handle 5 for a purpose which will be more fully explained hereinafter.

The valve chamber is included in a suction conduit 8 leading from the suction side of a conventional pump 21 to chamber 3, which is connected by a suction stud 12 to sheet separating means diagrammatically indicated by a suction foot 13. Similarly, the pressure side of the pump is connected by a pressure conduit 9 to chamber 3, which is further connected by a pressure stud 14 to pressure air consumers indicated as a sheet-loosening nozzle 15 and a blowing nozzle 16. Additional suction air and pressure air consumers such as auxiliary devices for separating, conveying, aligning, etc., of sheets in a stack 17 may, of course, be provided.

Measuring or control instruments indicated at 10 and 11 may be included in conduits 8 and 9.

Let it now be assumed that handle 5 is in the illustrated position, that is, in engagement with limit stop 6. The compartment 18a as defined by the slide 4 in the illustrated position then establishes a direct communication between the conduit portions leading from the pump to the chamber. As a result, the consumers are disconnected from the suction and pressure air supply, compartment 18 constituting a direct communication between studs 12 and 14. Accordingly, a new stack can be readied, adjustments may be effected at the machine or any other required adjustments can be carried out without stopping the pump.

When it is desired to supply the consumers 13, 15 and 16 with suction and pressure air respectively, handle 5 is turned into engagement with stop 7. The slide now occupies a position in which compartment 18 connects the air pressure via conduit 9, compartment 18 and stud 14 to the pressure air consumers and compartment 18a connects the suction side of the pump to the suction air consumers via conduit 8 and stud 12.

As is now evident, all necessary Or desired work can be effected on the machine and the accessories thereof without overloading pump 21 or causing wear and tear on the same and also without stopping the pump.

As is further evident, valve 2 can be installed at any desired location since it constitutes a self-contained structural unit.

While the invention has been described in detail with respect to a certain new preferred example and embodiment of the invention, it will be understood by those skilled in the art, after understanding the invention, that various changes and modifications may be made Without departing from the spirit and scope of the invention, and it is intended, therefore, to cover all such changes and modifications in the appended claims.

What is claimed is:

1. In a sheet processing machine having a suction air operated sheet feeder and a pressure air operated sheet separator a control device for controlling the flow of suction air and pressure air to sheet feeder and the separator respectively, said device comprising in combination:

(a) a common pump means having a suction side and a pressure side for supplying suction air to the sheet feeder and pressure air to the sheet separator;

(b) a suction conduit connecting the suction side of the pump means to the sheet feeder;

(c) a pressure conduit connecting the pressure side of the pump means to the sheet separator; and

(d) a valve means included in said conduits, said valve means being settable selectively into a position opening both said conduits for the fiow of pressure air and suction air to the sheet feeder and the sheet separator respectively, and into a position interconnecting said conduits on the side thereof leading to the pump means for opening a direct flow path from the pressure side of the pump means to the suction side thereof, while at the same time closing off communication between the pump suction and pressure conduits and the sheet feeder and sheet separator, respectively.

2. A device according to claim 1 wherein said valve means comprises a valve housing defining a chamber included in said conduits, and a movable valve member fitted in said chamber to define two closed compartments therein, said valve member being selectively movable between a first position in which the suction conduit is connected with the sheet feeder through one of said compartments and the pressure conduit is connected with the sheet separator through the other of said compartments, and a second position in which the portions of the suction conduit and the pressure conduit leading from the pump means to the chamber are directly interconnected by one of the compartments in the chamber, the valve member in the second position closing the conduit connections between the pump means and the sheet feeder and the sheet separator.

3. A device according to claim 2 wherein said valve means is a rotary slide valve comprising a housing ineluding a cylindrical chamber, a slide rotatably fitted in said chamber to define therein the compartments closed against each other, and external actuating means coupled with said slide to turn the same into either one of said positions.

References Cited UNITED STATES PATENTS 1,152,400 9/1915 Dennedy 230-22 1,865,110 6/1932 Johnson 230-46 X 2,210,144 8/1940 Day 103-41 X 2,490,418 12/1949 Collins et al. 230-46 X FOREIGN PATENTS 4,448 3/ 1905 Great Britain.

DONLEY J. STOCKING, Primary Examiner.

W. I. KRAUSS, Assistant Examiner.

US. Cl. X.R. 103-41 

